Heretofore a buccal tube as indicated in FIG. 4 was often used as an orthodontic buccal tube.
In the same figure, reference numeral 1 is a base portion of the buccal tube and 2 is the main body of the tube. In the main body 2 of the tube there are formed throughholes 3 and 4 having rectangular cross-sections, which traverse it in the longitudinal direction. The occlusal throughhole 3 is called the "main tube" and the gingival throughhole 4 is called the "auxiliary tube". A cover cap 5 is easily dismountably connected to the throughhole 3 serving as the main tube. Further, two tie wings 6 are formed on the occlusal side of the main body 2 of the tube, protruding therefrom in one body, and a hook 7 is added thereto on the gingival side.
FIG. 5 shows a state, in which the buccal tube described above is mounted on a first molar tooth of the lower jaw. In this case, the buccal tube is secured previously by welding at the base portion 1 to a band 9 fitted to the first molar tooth. The buccal tube or a bracket is secured directly by adhesion using an adhesive to other molar teeth. 10 indicates a rectangular wire for orthodontic treatment.
In the case where orthodontia is effected by using the buccal tube described above, the buccal tube is bonded on a tooth or welded on a band which is fitted to a tooth and the wire 10 is inserted in the throughhole 3 serving as the main tube.
In a buccal tube with torque the throughhole 3 described above having a rectangular cross-section is disposed with a certain inclination with respect to the tube base 1 and the buccal tube is so designed that an orthodontic force is produced by a torque generated after inserting the wire therein. The gingival throughhole 4 is used for an auxiliary wire pass.
The tie wings 6 above formed on the occlusal side of the main body 2 of the tube in one body, protruding therefrom, are used for passing a ligature 11 (or elastic module) between the gingival side portion of the main body 2 of the tube and, and the tie wings as indicated in FIG. 6, after having removed the cover cap 5 on the throughhole 3 serving as the main tube in order to prevent the wire from slipping out, i.e. as a portion for hooking the ligature.
The positional relation of the molar tooth of a patient, for which orthodontic treatment is required, is not, in most cases, in a good state. For this reason, even if the position of the buccal tube on the band is set so as to be most suitable, it happens often that the cusp of the opposite tooth is brought into contact with the tie wings described above so that the buccal tube cannot be set at a desired position, or even if it is set, the tie wings need to be removed thereafter by cutting by means of a cutting machine such as a dental engine, with a carborundum point.
Furthermore, in the case where the buccal tube is secured directly to the surface of a tooth by adhesion without a band, since the tube is constructed so that it cannot be easily held by means of a dental pincette, etc., it is also a disadvantage thereof that holding it, until the adhesive is hardened, is difficult.